1.5 DNA replication

Question 1

What is conservative replication theory?

Answer 1

The DNA molecule would be copied from the original, leaving the original DNA molecule as it was and having a new copy.

Question 2

What is dispersive replication theory?

Answer 2

Sections of the DNA molecule would be copied and spliced together, making each new DNA molecule a mix of original and new DNA.

Question 3

What is semi-conservative replication theory?

Answer 3

The two polynucleotide chains would part, and new nucleotides attach to each of the chains, leading to each new molecule having one original chain and one new one.

Question 4

Why was semi-conservative replication accepted?

Answer 4

The base pairs are complimentary so if the two strands separated, they would each make another complementary strand. The two new strands would be complimentary.

Question 5

What did Meselson and Stahl use as the source of DNA?

Answer 5

E.Coli

Question 6

Why did Meselson and Stahl use E.coli?

Answer 6

E.coli are easily grown in a flask of culture medium and replicate their cells (and DNA) every 20 minutes under optimal conditions.